A supramolecular magnetic and multifunctional Titriplex V-grafted chitosan organocatalyst for the synthesis of acridine-1,8-diones and 2-amino-3-cyano-4H-pyran derivatives.

Abstract

In this research, a new supramolecular magnetic modified chitosan, namely, Fe3O4@CS-TDI-Titriplex V, was designed and prepared conveniently by grafting diethylenetriaminepentaacetic acid (Titriplex V) onto a biopolymeric chitosan backbone having urethane, urea, ester and amide functional groups. The obtained magnetic biopolymeric nanomaterial was properly characterized by different spectroscopic, microscopic or analytical methods including FTIR spectroscopy, EDX spectroscopy, XRD, FESEM, TG-DTA and VSM. The application of the supramolecular Fe3O4@CS-TDI-Titriplex V nanocomposite as a heterogeneous solid acidic organocatalyst was investigated to promote the three-component synthesis of both acridinediones and 2-amino-3-cyano-4H-pyran derivatives as important pharmaceutical scaffolds under green conditions. The obtained nanomaterial exhibited proper catalytic activity in the above mentioned transformations through multicomponent reaction (MCR) strategies. The reactions proceeded very well in the presence of the Fe3O4@CS-TDI-Titriplex V solid acid nanomaterial in EtOH to afford the corresponding acridinediones and 2-amino-3-cyano-4H-pyran derivatives in high to excellent yields. The key advantages of the present protocol include the use of a renewable, biopolymeric and biodegradable solid acid as well as a simple procedure for the preparation of the hybrid material. Furthermore, the Fe3O4@CS-TDI-Titriplex V nanomaterial was used four times with a slight decrease in its catalytic activity.